from django.core.cache import cache
from django.db import models

from utils.models import BaseModel


# Create your models here.

class NavCategory(BaseModel):
    name = models.CharField(max_length=30,verbose_name='导航名称')
    display_name = models.CharField(max_length=30,verbose_name="导航显示名称")
    weight = models.IntegerField(default=0,verbose_name="导航图标")
    external_link = models.URLField(verbose_name="外链地址",blank=True)

    class Meta:
        verbose_name = "导航分类"
        verbose_name_plural = verbose_name
        db_table = "tb_nav_category"
        ordering = ["weight"]

    def __str__(self):
        return self.name

class CourseCategory(BaseModel):
    """
    课程分类
    """
    name = models.CharField(max_length=20,verbose_name="课程分类名称")
    level = models.IntegerField(verbose_name="课程分类级别")
    description = models.TextField(verbose_name="课程分类描述",null=True,blank=True)
    parent = models.ForeignKey('self',on_delete=models.CASCADE,verbose_name="父级分类",null=True,blank=True)

    class Meta:
        verbose_name = "课程分类"
        verbose_name_plural = verbose_name
        db_table = "tb_course_category"

    def __str__(self):
        return self.name

class Banner(BaseModel):
    title = models.CharField(max_length=200,verbose_name="标题")
    image = models.CharField(max_length=200,verbose_name="轮播图路径")
    link = models.URLField(max_length=200,verbose_name="轮播图链接")
    note = models.CharField(max_length=100,verbose_name="广告备注")

    class Meta:
        verbose_name = "轮播图"
        verbose_name_plural = verbose_name
        db_table = 'tb_banner'

    def __str__(self):
        return self.title

    def save(self,*args,**kwargs):
        """
        重写save方法，在保存数据时，自动清除缓存
        :param args:
        :param kwargs:
        :return:
        """
        super().save(*args,**kwargs)
#         清除缓存
        cache_key = "code_env_space:banner:list"
        cache.delete(cache_key)

    def delete(self,*args,**kwargs):
        """
        重写delete方法，在删除数据时，自动清除缓存
        :param args:
        :param kwargs:
        :return:
        """
        super().delete(*args,**kwargs)
#         清除缓存
        cache_key = "code_env_space:banner:list"
        cache.delete(cache_key)















